HD64F2149 Datasheet, PDF (437/1035 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

TCNT count
H'FF
Overflow
Overflow
Overflow
Overflow
H'00
WT/IT = 0
TME = 1
WOVI
WOVI
WOVI
WOVI
Time
Legend:
WOVI: Interval timer interrupt request generation
Figure 14.4 Operation in Interval Timer Mode
14.3.3 Timing of Setting of Overflow Flag (OVF)
The OVF flag is set to 1 if TCNT overflows during interval timer operation. At the same time, an
interval timer interrupt (WOVI) is requested. This timing is shown in figure 14.5.
If NMI request generation is selected in watchdog timer mode, when TCNT overflows the OVF
bit in TCSR is set to 1 and at the same time an NMI interrupt is requested.
ø
TCNT
Overflow signal
(internal signal)
H'FF
H'00
OVF
Figure 14.5 Timing of OVF Setting
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